Schottky barrier diodes, or simply Schottky diodes, are widely used in modern semiconductor devices. The Schottky diode enjoys lots of advantages such as a low forward voltage drop and a high switching speed. The Schottky diode is particular useful in radio-frequency applications, for example, energy harvest devices. Most of the time a semiconductor device may require a few Schottky diodes with different specifications for performing different tasks or fulfilling different performance requirements. Fabricating processes for such similar yet different Schottky diodes may be time-consuming and costly. Accordingly, it is desirable to improve existing manufacturing procedures of the Schottky diodes.